I have no idea why this happens. I know it's the Friends and Foes mod causing this because sometimes the offer is for buttercups, which are added by this mod. I only have one other mod revolving around villagers that adds new work stations, but I doubt it's that one because the new jobs are also affected by this. Unemployed villagers also have a trade menu with flowers, but it closes by itself instantly.
by Designer-Office4698